Wednesday, December 5, 2007

3.2.2 ROP

ROP, or retinopathy of prematurity, surprisingly is still quite prevalent. In older ophthalmology textbooks, ROP was referred to as retrolental fibroplasia and the cause was traced to excessive oxygen in the incubator. This occurred in the 1940s and 50s and was thought to be under control. However, with the recent advent of in-vitro fertilization and fertility drugs based on follicle-stimulating hormone and luteinizing hormone, multiple births have become relatively common. And with that, an increase of preemies. We often see on TV evening news, palm-sized infants inside the incubators with beaming parents looking on. While all lives must be celebrated, often unreported is a multitude of complications from pre-term births. The surviving babies often face a lifetime of health problems. And one of the problems is ROP.

In this day and age, excess oxygen in the incubator is no longer an issue, which is very carefully monitored. However, the development of the retina in pre-term babies is incomplete and for some reason, further development outside the womb is met with confusion. Often the blood vessels, reaching from the optic nerve to the peripheral retina, become fibrous that can pull off the retina (see the video below).

(Courtesy of National Eye Institute, NIH)

ROP is divided into 5 stages of increasing severity. Stage 5 is the most advanced that usually involves total retinal detachment. The video above illustrates such a case.

The treatment of ROP is essentially a repair, using laser, cryotherapy, or open-sky vitrectomy. We favor the more efficacious open-sky procedure in which the cornea is opened and the crystalline lens removed to expose the rest of the eye to the sky. Then the fibrous tissues are removed and the retina re-attached. The resulting aphakia, unlike that of the age-related cataract, is corrected with a contact lens first, then an IOL later in life. The visual acuity is usually quite good, often in the 20/40 - 20/60 range.

To avoid ROP and related health problems, perhaps higher-order births should be discouraged. Certainly multiple births should be managed by OBs and pediatric nurses with specialty training. They must not yet be treated as normal births.